Carré de Polybe

The greeks are at the origin of the square of Polybe.

Polybe was a greek writer, he was at the origin of the first method of substitution cipher. The square of Polybe is a system based on a square of 25 squares. Each letter is represented by 2 figures.

So e=15,v=51

Polybe allowed to transmit messages over long distances. There are different interesting characteristics : Conversion of letters in numbers,reduction of numbers of symbols and representation of each letter by 2 separate elements.

Unfortunatly Polybe didn’t relate any use of is revolutionary process.